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Goddard, C.

Publications and source records attributed to Goddard, C..

2 recordsLinked to original sources

An Open-Source 3D-Printed Vacuum Manifold for Automated DNA Isolation in the Opentrons Flex and OT-2

Laboratory automation is increasingly being adopted in academic research to improve throughput, reproducibility, and integration with computational workflows. A common bottleneck in molecular biology workflows is the isolation of DNA, typically performed with spin-column kits relying on centrifugation or vacuum. Existing automation solutions depend on magnetic separation systems requiring costly additional modules and specialist kits, making them impractical for laboratories that perform large numbers of extractions only occasionally. Here we present an open-source, 3D-printed vacuum manifold compatible with the Opentrons family of liquid handling robots that enables automated spin-column DNA isolation for up to 24 samples per run (96 with four manifolds in series). The manifold can be manufactured for approximately $2 using standard ABS filament and is compatible with widely available spin-columns, requiring no additional specialist reagents. Using this system, hands-on time for 24 plasmid minipreps was reduced by 80% compared to manual centrifugation and vacuum protocols. The automated workflow demonstrated comparable or greater plasmid yields and eliminated failed recoveries. All design files, labware definitions, and Opentrons protocols are released under the CERN Open Hardware Licence or MIT License. This device lowers the cost barrier to automated DNA purification for academic laboratories worldwide.

molecular biology↗

NMR structure of the carboxy-terminal domain of the Ea22 pro-lysogenic protein from lambda bacteriophage

The ea22 gene resides in a relatively uncharacterized region of the lambda bacteriophage genome between the exo and xis genes and is among the earliest genes transcribed upon infection. In lambda and Shiga toxin-producing phages found in enterohemorrhagic E. coli (EHEC) associated with food poisoning, Ea22 favors a lysogenic over lytic developmental state. The Ea22 protein may be considered in terms of three domains: a short amino-terminal domain, a coiled-coiled domain, and a carboxy-terminal domain (CTD). While the full-length protein is tetrameric, the CTD is dimeric when expressed individually. Here, we report the NMR solution structure of the Ea22 CTD that is described by a mixed alpha-beta fold with a dimer interface reinforced by salt bridges. A conserved mobile loop may serve as a ligand for an unknown host protein that works with Ea22 to promote bacterial survival and the formation of new lysogens. From sequence and structural comparisons, the CTD distinguishes lambda Ea22 from homologs encoded by Shiga toxin-producing bacteriophages.

molecular biology↗